Alcoholism in family linked to obesity

10th January 2011

US researchers say that a family history of alcoholism is associated with the risk of obesity.

Scientists at the Washington University School of Medicine in St Louis said data accumulated from the last few years shows a growing link between a family history of alchohol dependency and obesity risk.

Writing in the Archives of General Psychiatry, researchers said that a higher percentage of males and females with a family history of alcoholism were found to be obese in 2002 than in 1992.

According to study first author Richard Grucza, researchers looked at cross-heritability, to address the question of whether the predisposition to one condition also might contribute to other conditions.

Alcoholism and drug abuse are widely accepted to be cross-heritable, for example.

While the study had demonstrated cross-heritability between alcoholism and obesity, it had also found that other factors had boosted the risks over the past decade.

He said some of the risks, therefore, must be a function of the environment.

Obesity is defined as a body mass index (BMI) of at least 30, according to which 15% of the US population was obese in the late 1970s, compared to 33% in 2004.

Obesity carries with it a significantly higher risk of high blood pressure, several cancers, stroke, heart disease and diabetes.

Grucza said that study participants, particularly women, with a family history of alcoholism had a higher risk of obesity.

He said food consumed nowadays typically contained more calories than it did in the 1970s and 1980s, especially in the form of sugar, salt and fat, which appeal to the brain's reward centres.

Therefore, researchers wanted to investigate whether people with a greater predisposition to addiction generally might also be vulnerable to overconsumption of such foods.

The study examined family history in particular, relating to alcoholism.

In 2001 and 2002, women with such a family history were 49% more likely to be obese than those with no such history.

The link was also present in men, but not as strikingly.

The findings suggested some people may be swapping one addiciton for another, especially if certain individuals are put off alcohol by witnessing its abuse in their own families.

People who actually have alcoholism, by contrast, are more likely to be malnourished, or under-nourished, because they replace their food intake with alcohol.

The link between family history of alcoholism and obesity remained, even after other factors like smoking, age, educational level and alcohol intake were controlled for.

Researchers speculated that a change in the food environment brought the association about, as a growing range of hyper-palatable foods appealed to people with addictive tendencies.

They suggested more liaison between alcohol, addiction and obesity researchers.